/*
 * Copyright 2011 Clean GWT
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */
package com.cleangwt.validation.client;

/**
 * A base {@link Validation} provides the {@link #isValid(Object[])} method, just define the
 * validation logic and return ture for reporting <code>null</code> meesage, return false to report
 * the predefined error message.
 * 
 * @author Jess
 * @version 1.0
 * @since 1.0
 */
public abstract class BaseValidation extends Validation {
  private final String message;

  /**
   * Creates a base validaiton with the given message and groups.
   * 
   * @param message the message for the validated value is invalid
   * @param groups the groups
   */
  public BaseValidation(String message, String... groups) {
    super(groups);
    this.message = message;
  }

  /**
   * Checks whether the given value(s) is valid.
   * 
   * @param values the values to be verified
   * @return true for valid, false for invalid
   */
  abstract protected boolean isValid(Object[] values);

  @Override
  protected String validate(Object[] values) {
    if (isValid(values)) {
      return null;
    }
    return message;
  }
}
